Heather Strube was in a bitter custody dispute with her husband Steven in April 2009 when she was confronted by a "man" in a Georgia parking lot who put a gun to her head and shot her.
That man, prosecutors allege, was Heather Strube's mother-in-law Joanna Hayes disguised in a wig and moustache.
And today Steven Strube testified in his mother's murder trial.
Jurors listened to a phone recording of Steven Strube asking his mother, "why did you do it."
Today, Steven Strube told attorneys that he no longer believed his mom murdered his wife.
Heather and Steven Strube were battling in court over custody of their 18-month-old son Carson at the time of the murder. The couple agreed to meet in the parking lot of a Target store in Snellville, Ga., on April 26, 2009 so Steven could hand over Carson to Heather.
After the handover, Steven drove away and Heather strapped the boy into a car seat when the gunman arrived at Heather Strube's car, put a gun to her head and shot her. The boy was unharmed.
Prosecutors allege Hayes donned a disguise and shot Strube because she didn't want her daughter-in-law to have custody of her grandson.
"This person pulls out a gun, places it on Heather's forehead, and shoots her," said prosecuting attorney Christa Kirk during opening statements last week. "The defendant, she didn't like Heather. She didn't want Heather to have custody of Carson in the divorce."
Today, a witness testified that Strube seemed to recognize her murderer.
"The woman recognized this person...surprised to run into them in the parking lot. They weren't expecting someone to be there, but kind of look at them with a little bit of shock," Kiersten Rom testified. Rom was with her parents on the day of the murder.
"I heard a popping noise and then the woman that was standing by the car clutched her stomach and then collapsed to the ground," Rom testified.
Rom testified that she was unsure if the shooter was a man or a woman.
A friend of Strube's testified that the woman was scared of her mother-in-law and didn't feel physically safe around the woman.
Hayes' defense team denies her involvement in the murder.
"The motive that Joanna killed her daughter-in-law because of some custody is going to unravel during the trial," said defense attorney Bruce Morris during opening statements. "It was not her in the parking lot that day."
Testimony from last week revealed Hayes had once described how she would commit the perfect murder. Former co-worker Paul Pinzino testified that Hayes said she would use an unregistered revolver "because they don't jam."
Hayes allegedly told Pinzino that she'd buy the gun from someone at a construction site and that she'd already bought three guns before at construction sites. Hayes reportedly worked in construction and would make extra cash delivering flowers for her daughter-in-law's floral company.
To hide evidence of the crime, Hayes told Pinzino she would melt the gun.
"She had a shop behind her house..and she said she could actually use the tools in that shop to destroy the weapon," Pinzino testified.
Police have never found the murder weapon used to gun down Heather Strube. Nearly eight months after the crime, Hayes was arrested and charged with murder in December of 2009.
Snelville police said that surveillance video revealed that the killer wore a wig and fake mustache, ABC Affiliate WSB TV reported. Surveillance video shows what looks like a man wearing khaki pants with a shirt tucked into the pants.
Prosecutors allege that a wig fiber was found in Hayes' truck.
One witness testified that someone wearing an "afropuff" wig ran around the Target to the parking lot of a hotel following the crime and drove away in a white pickup truck.
ABC Affiliate WSB TV contributed to this report.